5. Markel Susaeta (11 years, 7 months)
Susaeta joined Athletic Bilbao's youth academy in 1997 and hasn't looked back since. After spending a season with the B team, he broke into the first team in 2007. He has been somewhat of a permanent player, having played in more than 490 competitive games, scoring more than 50 goals.
4. Marcelo (12 years, 1 month)
Marcelo joined Real Madrid in the January transfer window of 2007, having graduated from Fluminese's academy and has been a regular starter since his breakthrough season in 2010/11.
3. Bruno Soriano (12 years, 8 months)
Bruno has dedicated his whole footballing life to one club, much like Susaeta. He came through Villarreal's youth system and made his competitive debut for them in July 2006. The defensive midfielder is known for his pinpoint interceptions and has therefore been a constant presence in the starting XI for over a decade.
2. Sergio Ramos (13 years, 7 months)
Sergio Ramos' transfer from Sevilla to Real Madrid in 2005 for €27 million was a then record deal for a Spanish defender. He was chosen, undisputedly, as captain of the side after Iker Casillas' departure. In 2013, he became Spain's youngest ever player to reach 100 caps. Ramos is widely regarded as one of the world's best defenders but has also received recognition for his passing and goal scoring skills, netting 59 times for Los Blancos.
1. Lionel Messi (13 years, 10 months)
How to describe Lionel Messi? Barcelona's little magician came through the club's La Masia academy where he was tipped to go on to great things... and that he did! The 31-year-old boasts several records and his list of achievements is almost endless. To name a few, he has scored the most goals in La Liga (404), most goals in a La Liga season (50), most goals in a calendar year (91) and most goals in El Clasico (26). To try and quantify his excellence, he has scored over 670 senior career goals for club and country. An absolutely staggering figure.